At Thu, 29 Mar 2007 05:56:50 -0500, Nagalla, Hari wrote: > > Hello, > > I am new to ALSA, so some help from experienced folks would help.. > > We are trying to develop ALSA support for our DSP based mixer. In our > architecture DSP performs the mixing, sample rate conversion etc. My > question is how, can does the user space applications exercise > controlling individual PCM stream to the mixer? Ex: individual stream > gain control, individual stream mute, etc.. Any user space example code > would be useful too.. Most drivers create PCM volume controls with IFACE_PCM tag, and set up the volume appropriately at each PCM open, or let alsa-lib configs to set up the initial volumes. Usually, the control element index corresponds to the PCM substream number. The controls with IFACE_PCM are not visible from normal mixer apps. (The mixer sees only IFACE_MIXER elements.) So, if you need a dynamic control of such elements, you'll likely need a special program to access the corresponding elements. Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
